Curvature

[Ignition]

Does exist a system to calculate how mass creates a curvature in relativity, and how it creates redshift?

[HallsofIvy]

I presume that, since you talk about "curvature in relativity", you are aware of the Einstein Curvature Tensor. One uses the mass distribution to calculate the mass-energy tensor, from that derives the metric tensor, then the Curvature tensor from the metric tensor.

(I'm not claiming any one of those steps is an easy calculation!)